Document Type
Technical Report
Date of this Version
2-1999
Publication Source
The Plant Cell
Volume
11
Issue
2
Start Page
207
Last Page
221
DOI
10.1105/tpc.11.2.207
Abstract
Lesions in brassinosteroid (BR) biosynthetic genes result in characteristic dwarf phenotypes in plants. Understanding the regulation of BR biosynthesis demands continued isolation and characterization of mutants corresponding to the genes involved in BR biosynthesis. Here, we present analysis of a novel BR biosynthetic locus, dwarf7 (dwf7). Feeding studies with BR biosynthetic intermediates and analysis of endogenous levels of BR and sterol biosynthetic intermediates indicate that the defective step in dwf7-1 resides before the production of 24-methylenecholesterol in the sterol biosynthetic pathway. Furthermore, results from feeding studies with 13C-labeled mevalonic acid and compactin show that the defective step is specifically the Δ7 sterol C-5 desaturation, suggesting that dwf7 is an allele of the previously cloned STEROL1 (STE1) gene. Sequencing of the STE1 locus in two dwf7 mutants revealed premature stop codons in the first (dwf7-2) and the third (dwf7-1) exons. Thus, the reduction of BRs in dwf7 is due to a shortage of substrate sterols and is the direct cause of the dwarf phenotype in dwf7.
Copyright/Permission Statement
© 1999 American Society of Plant Physiologists. Reproduced with permission.
Recommended Citation
Choe, S., Noguchi, T., Fujioka, S., Takatsuto, S., Tissier, C. P., Gregory, B. D., Ross, A. S., Tanaka, A., Yoshida, S., Tax, F. E., & Feldmann, K. A. (1999). The Arabidopsis dwf/ste1 Mutant is Defective in the Δ7 Sterol C-5 Desaturation Step Leading to Brassinosteroid Biosynthesis. The Plant Cell, 11 (2), 207-221. http://dx.doi.org/10.1105/tpc.11.2.207
Included in
Biology Commons, Nucleic Acids, Nucleotides, and Nucleosides Commons, Plant Breeding and Genetics Commons
Date Posted: 14 July 2017
This document has been peer reviewed.
Comments
At the time of this publication, Dr. Gregory was affiliated with the University of Arizona, but he is now a faculty member at the University of Pennsylvania.